体外鉴定的禽流感病毒T细胞表位的免疫效果研究

The Immunologic Effect of Identified Avian Influenza Viruses T Cell Epitopes in vitro

为验证来源于禽流感病毒的、可与鸡MHCⅠ类分子结合的九肽KILTIYSTV和LLLAIVSLV的免疫原性,使用TIGECPKYV、LLLAIVSLV和KILTIYSTV 3条多肽免疫BALB/c小鼠,加强免疫时和加强免疫1、2、3、4、5周后分别采血,流式细胞术测定免疫前后小鼠外周抗凝血中CD8+淋巴细胞的变化情况;加强免疫后14 d进行MTT试验;首次免疫3周后进行DTH试验;ELISA检测免疫前后小鼠分泌IFN-γ的变化情况。结果表明,KILT-IYSTV、LLLAIVSLV、TIGECPKYV免疫后分别引起CD8+T淋巴细胞4.2%、4.0%和0.2%的额外增殖。KILTIYSTV和LLLAIVSLV免疫组的IFN-γ的增长和迟发型变态反应均显著高于对照组。简言之,与重建的MHCⅠ类分子结合的多肽KILTIYSTV和LLLAIVSLV可以刺激小鼠产生特异性CTL反应,而不结合的多肽TIGECPKYV刺激小鼠未产生特异性CTL反应。

To identify whether avian influenza viruses （AIV） derived peptides KILTIYSTV and LLLAIVSLV are authentic T cell epitopes, 6 weeks old BALB/c mice were immunized with KILTIYSTV, LLLAIVSLV and KILTIYSTV respectively. The blood samples were collected at the 1st, 2nd, 3rd, 4th and 5th week after reimmunization. CD8^＋ T cell was detected by fluorescence activated cell sorting （FACS）. MTT test was carried out at 14 days after boost immunization; Peptide-specific delayed-type of hypersensitivity assay was done on third weeks after the first immunization. Proliferation of secreted IFN-γ in serum of mice was detected by ELISA. The results showed that the peptides KILTIYSTV, LLLAIVSLV and TIGECPKYV stimulated 4.2%, 4.0% and 0.2% growth of peptide-specific CD8^＋ T lymphocyte, Secreted IFN-γ level, specific delayed-type of hypersensitivity （DTH） response and MTT test in KILTIYSTV and LLLAIVSLV group were all significantly higher than that of control groups. In a word, animal immunity experiment revealed that two T cell epitopes KILTIYSTV and LLLAIVSLV could lead to specified CTL reaction, but the peptide TIGECPKYV that don＇t bind with reconstructed MHC Ⅰ couldn＇t.